Overturn preventing device

ABSTRACT

Providing an overturn preventing device which can easily determine whether or not the damper is properly mounted. The overturn preventing device is mounted between a top surface of a piece of furniture (an article) and a ceiling. The overturn preventing device includes a damper. The damper includes a cylinder, a rod, a piston and a rod cover. The cylinder encloses a hydraulic fluid (operating liquid) and a gas. The rod is reciprocably inserted into the cylinder. The piston is slidably housed in the cylinder. A proximal end of the rod is coupled to the piston. The rod cover has one of two ends coupled to a distal end side of the rod thereby to be reciprocable together with the rod. The opening side end of the rod cover is located on a side of the bottom side end of the cylinder relative to the opening side end of the cylinder when the piston is immersed in the operating liquid.

TECHNICAL FIELD

The present invention relates to an overturn preventing device.

BACKGROUND ART

Patent Document 1 discloses a conventional overturn preventing device. This overturn preventing device is mounted between a top surface of a piece of furniture installed on a floor surface and a ceiling. The overturn preventing device includes a damper which is extended and contracted to generate a damping force. When the furniture is tilted by shaking of an earthquake or the like, the damper is contracted to generate a damping force with the result that the overturn preventing device can prevent the furniture from overturn.

PRIOR ART DOCUMENT Patent Documents

Patent Document 1: Japanese Patent Application Publication No. JP 2015-6330

SUMMARY OF THE INVENTION Problem to be Overcome by the Invention

In the overturn preventing device of Patent Document 1, when a distance between the top surface of the furniture and the ceiling is large, a piston provided in a cylinder would be disposed in a compressed gas which is enclosed above a hydraulic fluid in the cylinder depending on an amount of extension of the damper. In the case where the overturn preventing device is mounted in such a state, when the furniture is tilted by shaking of an earthquake or the like, the damper does not generate a damping force until the damper is contracted so that the piston is moved into the hydraulic fluid. Consequently, there is a possibility that the damping force of the damper does not effectively act on the furniture with the result that the furniture would be overturned.

Thus, the damper needs to be used in a state such that an appropriate damping force can be generated. However, it is difficult, in many cases, to determine from an appearance whether or not the damper is in such a state.

The present invention was made in view of the above-described circumstances in the conventional art and has an object to provide an overturn preventing device which can be easily determined whether or not it is properly mounted.

Means for Overcoming the Problem

An overturn preventing device of the present invention is mounted between a top surface of an article installed on an installation surface and a ceiling. The overturn preventing device includes a damper. The damper includes a cylinder, a rod, a piston and a rod cover. The cylinder is formed into a bottomed cylindrical shape and encloses an operating liquid and a gas. The rod is inserted into the cylinder to be reciprocable in a central axis direction and protrudes upward from one of two ends of the cylinder. The piston is housed in the cylinder to be slidable in the central axis direction. A proximal end of the rod is coupled to the piston. The rod cover is cylindrical and extends on a central axis line of the rod. The rod cover has two ends one of which is coupled to a distal end side of the rod thereby to be reciprocable in the central axis direction of the rod together with the rod. The other end of the rod cover is located on a side of the other end of the cylinder relative to the one end of the cylinder when the piston is immersed in the operating liquid.

The overturn preventing device in accordance with the invention may further include a cylinder side base and a connecting member. The cylinder side base is coupled to the other end of the cylinder and abuts against the top surface of the article or the ceiling. The connecting member connects the cylinder side base or the cylinder and the rod cover in a state where the damper is contracted.

In the overturn preventing device in accordance with the invention, the cylinder side base may be coupled to the damper via a rotating shaft rotatably supporting the damper. The cylinder side base may have a scale. The scale indicates an angle about the rotating shaft. The connecting member may be rotatably supported by the rotating shaft thereby to be connected to the cylinder side base. The connecting member may have a pointing part. The pointing part is rotated with rotation of the connecting member to point to the scale.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic side view of an overturn preventing device of a first embodiment, mounted between a top surface of furniture and a ceiling;

FIG. 2 is a schematic side view of the overturn preventing device of the first embodiment in a contracted state;

FIG. 3 is a schematic front view of the overturn preventing device of the first embodiment in the contracted state;

FIG. 4 is a partial sectional view of a damper and a cylinder side base of the overturn preventing device of the first embodiment;

FIG. 5 is a schematic diagram of the overturn preventing device of the first embodiment placed on the top surface of the furniture;

FIG. 6 is a schematic diagram of an example of a case where the damper exerts a proper damping force in the overturn preventing device of the first embodiment;

FIG. 7 is a schematic diagram of an example of a case where the damper does not exert a proper damping force;

FIG. 8 is a schematic sectional view of a major part of the overturn preventing device of a second embodiment;

FIG. 9 is a schematic sectional view of a major part of the overturn preventing device of another embodiment (No. 1); and

FIG. 10 is a schematic sectional view of a major part of the overturn preventing device of further another embodiment (No. 2).

BEST MODE FOR CARRYING OUT THE INVENTION

A first embodiment of the overturn preventing device, in accordance with the present invention will be described with reference to the drawings.

First Embodiment

At least one overturn preventing device 1 of the first embodiment is mounted between a top surface of a piece of furniture F (exemplified as an article in the invention) and a ceiling C, as illustrated in FIG. 1. The overturn preventing device 1 prevents overturn of the furniture F by use of a damping force when the furniture F is tilted upon occurrence of shaking of an earthquake or the like. The furniture F is installed on a floor surface (not illustrated) serving as an installation surface while a rear surface of the furniture F is opposed to a wall surface W vertically extending from the floor surface. The furniture F is formed into a rectangular parallelepiped shape and has a door, a drawer (neither illustrated) and the like in a front (a right side as viewed in FIG. 1), so that clothes, accessories and the like can be housed in the furniture F. The furniture F has a rectangle-shaped horizontal section long in a right-left direction (a depthwise direction in FIG. 1). When the overturn preventing device 1 is not mounted on the furniture F, the furniture F would possibly be tilted frontward (rightward in FIG. 1) by shaking of an earthquake or the like thereby to be overturned.

The overturn preventing device 1 includes a damper 10 as illustrated in FIGS. 1 to 3. The overturn preventing device 1 also includes a pair of bases 21 and 22, and a connecting member 31. The damper 10 has a furniture F side end and a ceiling C side end and imparts a biasing force in a direction such that the ends thereof depart from each other. The bases 21 and 22 are respectively coupled to the ends of the damper 10. The base 21 abuts against the top surface of the furniture F, and the base 22 abuts against the ceiling C. The connecting member 31 prevents extension of the damper 10 thereby to maintain the damper 10 in a contracted state.

The damper 10 includes a cylinder 11, a rod 13, a piston 14 and a rod cover 16. The damper 10 also includes a rod guide 12 and a damping part 15. The cylinder 11 is formed into a bottomed cylindrical shape. A Hydraulic fluid L (exemplified as an operating liquid in the invention) and a compressed gas G (exemplified as a gas in the invention) are enclosed in the cylinder 11. The rod guide 12 closes an opening of the cylinder 11. The rod 13 is inserted through an opening side end of the cylinder 11 into the cylinder 11 to be reciprocable in a central axis direction and protrudes from the opening side end of the cylinder 11. The rod 13 has a proximal end side inserted into the cylinder 11. Furthermore, the rod 13 is slidably inserted through the rod guide 12. The piston 14 is slidably housed in the cylinder 11. The proximal end of the rod 13 is connected to the piston 14. The piston 14 is provided so as to divide an interior of the cylinder 11 into a rod side pressure chamber 11A in which the proximal end of the rod 13 is housed and a counter-rod side pressure chamber 11B.

The damping part 15 imparts resistance to a flow of fluid moving between the rod side pressure chamber 11A and the counter-rod side pressure chamber 11B. The damping part 15 has an orifice 15A and a check valve 15B. The orifice 15A and the check valve 15B are respectively provided in flow passages communicating between the rod side pressure chamber 11A and the counter-rod side pressure chamber 11B. The check valve 15B allows the fluid to flow from the rod side pressure chamber 11A to the counter-rod side pressure chamber 11B and blocks the reverse flow. The orifice 15A and the check valve 15B are disposed in the piston 14.

The damper 10 is a compression damper in which a damping force generated during an extending operation is smaller than a damping force generated during a contracting operation. The contracting operation of the damper 10 refers to an operation which reduces an amount of protrusion of the rod 13 from the cylinder 11 (an entire length of the damper 10). The extending operation of the damper 10 refers to an operation which increases an amount of protrusion of the rod 13 from the cylinder 11 (an entire length of the damper 10). Furthermore, a gas pressure of the compressed gas G enclosed in the cylinder 11 causes a force to act in the extending direction of the damper 10. By the action of the compressed gas G, the damper 10 imparts a biasing force in such a direction that the lower end of the cylinder 11 serving as the furniture F side end and the upper end of the rod 13 serving as the ceiling C side end depart from each other.

The following will describe a mechanism of generating a damping force of the damper 10 by the damping part 15. The orifice 15A imparts resistance to the flow of hydraulic fluid L between the rod side pressure chamber 11A and the counter-rod side pressure chamber 11B with both extending and contracting operations of the damper 10. The check valve 15B allows the hydraulic fluid L to flow from the rod side pressure chamber 11A to the counter-rod side pressure chamber 11B and blocks the reverse flow. Accordingly, the damper 10 has two flow paths of the hydraulic fluid L from the rod side pressure chamber 11A to the counter-rod side pressure chamber 11B during the extending operation, that is, one flow path including the orifice 15A and the other flow path including the check valve 15B. On the other hand, the damper 10 has only one flow path of the hydraulic fluid L from the counter-rod side pressure chamber 11A to the rod side pressure chamber 11B through the orifice 15A during the contracting operation. Accordingly, the damping force generated by the damper 10 during the extending operation is smaller than the damping force generated by the damper 10 during the contracting operation.

The rod cover 16 is formed into the shape of a cylinder extending on a central axis line of the rod 13. The rod cover 16 has an end coupled to the distal end side of the rod 13 (the upper end side in FIGS. 1 to 3). In more detail, as illustrated in FIGS. 2 and 3, the rod cover 16 is formed into a bottomed cylindrical shape and disposed such that a bottom side end of the rod cover 16 faces the distal end side of the rod 13, and an opening side end of the rod cover 16 faces the proximal end side of the rod 13. The bottom side end of the rod cover 16 is coupled to the distal end side of the rod 13. The cylindrical rod cover 16 has an inner diameter that is set to be larger than an outer diameter of the cylinder 11. As a result, the rod cover 16 can cover an outer peripheral surface of the cylinder 11 when the damper 10 is contracted. Furthermore, the rod cover 16 is reciprocated with the rod 13 in the central axis direction of the rod 13 since the rod cover 16 is coupled to the distal end side of the rod 13. In other words, the rod cover 16 moves together with the rod 13 with the reciprocation of the rod 13 in the central axis direction. Furthermore, the opening side end of the rod cover 16 is formed with an engaged hole 16A with which a cover side engaging part of a connecting member 31 which will be described later is engaged.

The cylinder side base 21 is coupled via a joint 18 to the bottom of the cylinder 11. The rod side base 22 is coupled via another joint 18 to the distal end of the rod 13. In other words, the cylinder side base 21 is coupled via the joint 18 to the cylinder side end of the damper 10, and the rod side base 22 is coupled via the joint 18 to the rod side end of the damper 10. The cylinder side base 21 abuts against the top surface of the furniture F. The rod side base 22 abuts against the ceiling C. The damper 10 is mounted between the top surface of the furniture F and the ceiling C with the rod side end thereof being directed to the ceiling C side. The cylinder side base 21 and the rod side base 22 are provided to be rotatable relative to the damper 10. The cylinder side base 21 and the rod side base 22 substantially have the same form and the same structure.

The joints 18 are respectively provided on both ends of the damper 10, as described above. Each joint 18 is formed by bending a flat plate-shaped metal fitting as illustrated in FIG. 4. The joints 18 are respectively connected to the bottom of the cylinder 11 and the distal end of the rod 13. Each joint 18 is formed with a through hole 18A extending therethrough in a direction perpendicular to an axis line of the damper 10.

The cylinder side base 21 and the rod side base 22 each have a base body 23, a pin 24, a stop ring 25, and bush 26. Since the cylinder side base 21 and the rod side base 22 have substantially the same form and the same structure as described above, the cylinder side base 21 will be described in the following.

As illustrated in FIG. 4, the base body 23 has a hollow interior. The base body 23 has an insertion hole 23A. The pin 24 serving as the rotating shaft member is inserted through the insertion hole 23A. The pin 24 has a shaft part 24A inserted from one side of the insertion hole 23A of the base body 23 to be penetrate therethrough. The stop ring 25 is fitted with a distal end of the shaft part 24A at the other side of the insertion hole 23A. The pin 24 has a central axis which serves as a rotation axis of the damper 10 in each of the bases 21 and 22. A base side engaging part of the connecting member 31 which will be described later is engaged with a proximal end of the pin 24. The proximal end and the distal end of the pin 24 have substantially the same diameter, and the base side engaging part is engageable with either proximal or distal end of the pin 24.

Furthermore, a scale 23B is formed on a side surface of the base body 23. The scale 23B indicates an angle about a central axis of an insertion hole 23A through which the pin 24 serving as a rotating shaft is inserted. The scale 23B is formed as two marks indicating angles of 15 degrees and 25 degrees about the rotation axis with respect to the direction perpendicular to the bottom surface (the lower surface in FIG. 4) of the base body 23 and servers as a rough indication of an inclination angle of the damper 10 when the overturn preventing device 1 is to be installed.

The bush 26 is substantially cylindrical in shape as illustrated in FIG. 4 and is elastic. The bush 26 has a length that is set in a manner such that slight gaps are respectively defined between both end surfaces thereof and the base body 23 when attached to the base body 23. The bush 26 is formed with a concave portion 26A going around a central part of the outer peripheral surface thereof. The concave portion 26A has an outer diameter that substantially equals an inner diameter of the through hole 18A formed through the joint 15 of the damper 10. The bush 26 has portions rising from both ends of the concave portion 26A which portions have outer diameters larger than the inner diameter of the through hole 18A of the joint 18. Furthermore, both ends of the bush 26 have respective outer peripheral surfaces 26B the diameters of which are outwardly reduced. As a result, the bush 26 is inserted into the through hole 18A of the joint 18 of the damper 10 while being elastically deformed. The concave portion 26A is then fitted to the through hole 18A so that the bush 26 is attached to the joint 18 of the damper 10.

The central part of the bush 26 has an inner diameter slightly larger than an outer diameter of the shaft part 24A of the pin 24. Furthermore, both ends of the bush 26 have inner peripheral surfaces 26C the diameters of which are outwardly enlarged. Accordingly, the bush 26 is rotatable about the shaft part 24A of the pin 24. Furthermore, the bush 26 is inclinable with respect to the shaft part 24A of the pin 24 to the extent that the inner peripheral surfaces 26C of both ends thereof having enlarged diameters abut against an outer peripheral surface of the shaft part 24A of the pin 24. In other words, the damper 10 with the bush 26 attached to the joint 18 is rotatable about the shaft part 24A of the pin 24 and swingable in a direction intersecting the rotation direction. Furthermore, the damper 10 can be swung more largely in the direction intersecting the rotation direction by the elastic deformation of the bush 26.

When the piston 14 is immersed in the hydraulic fluid L, the opening side end of the rod cover 16 is located on a side of the bottom side end of the cylinder 11 relative to the opening side end of the cylinder 11. In other words, the opening side end of the rod cover 16 is located between the opening side end and the bottom side end of the cylinder 11 when the piston 14 is immersed in the hydraulic fluid L. Furthermore, it can also be said that a lower end of the rod cover 16 is located below an upper end of the cylinder 11 when the piston 14 is immersed in the hydraulic fluid L. The damper 10 exerts a proper damping force in this state. Furthermore, an entire part of the rod 13 protruding from the cylinder 11 is covered by the rod cover 16.

The connecting member 31 connects the cylinder side base 21 and the rod cover 16 thereby to restrict the extension of the damper 10. As illustrated in FIGS. 2 and 3, the connecting member 31 is formed by bending a plate-shaped member or processing the plate-shaped member in another manner. The connecting member 31 has a base side engaging part 31A and a cover side engaging part 31B. The base side engaging part 31A is a hole formed in one end side of the connecting member 31. The base side engaging part 31A is engaged with the proximal end of the pin 24 of the cylinder side base 21. The cover side engaging part 31B is formed on the other end side of the connecting member 31. The cover side engaging part 31B protrudes from one side of the plate-shaped connecting member 31 in the shape of a protrusion and is engaged with the engaged hole 16A formed in the rod cover 16. The base side and cover side engaging parts 31A and 31B are detachably engaged with the cylinder side base 21 and the rod cover 16, respectively. The connecting member 31 connects the cylinder side base 21 and the rod cover 16 in a state close to where the damper 10 is most contracted. While connecting the cylinder side base 21 and the rod cover 16, the connecting member 31 is rotated with rotation of the damper 10 relative to the cylinder side base 21 with the pin 24 as a rotation axis.

Furthermore, the connecting member 31 has a pointer 31C as illustrated in FIGS. 2 and 3. The pointer 31C is formed by sharpening a distal end of the connecting member 31 located at the base-side engaging part 31A side into a wedge shape. The pointer 31C points to the scale 23B formed on the side surface of the base body 23. Since the proximal end of the pin 24 with which the base side engaging part 31A is engaged is located inside the side surface of the base body 23 (refer to FIG. 4), the connecting member 31 is bent into a crank shape at a part thereof located between the base side engaging part 31A and the pointer 31C.

The overturn preventing device 1 having the above-described construction will be mounted between the top surface of the furniture F and the ceiling C in the following manner. In the overturn preventing device 1 in an initial state before the mounting, the rod cover 16 and the cylinder side base 21 are connected by the connecting member 31, and the damper 10 is held in the contracted state, as illustrated in FIGS. 2 and 3. In this contracted state of the damper 10, the connecting member 31 is rotatable with the damper 10 about the central axis of the pin 24 serving as the rotating shaft.

First, the overturn preventing device 1 is placed on the top surface of the furniture F and the cylinder side base 21 is caused to abut against the top surface of the furniture F. At this time, the overturn preventing device 1 is placed so that the shaft part 24A (the rotating shaft) of the pin 24 of the cylinder side base 21 is perpendicular to a direction in which the furniture F is tilted by shaking of an earthquake or the like (the right direction in FIG. 5). In other words, the cylinder side base 21 is placed on the top surface of the furniture F so that the rotation axis of the damper 10 is parallel to an axis of rotation center of the tilt of the furniture F.

The upper end of the damper 10 is then inclined frontward so that an inclination angle of the damper 10 with respect to the vertical direction is adjusted to be between 15° and 25°. In the first embodiment, the inclination angle can be adjusted so that the pointer 31C of the connecting member 31 which is inclined according to the inclination of the damper 10 points to the angular range (the range between 15° and 25°) indicated by the scale 23B. The angular range indicated by the scale 23B is set as a proper angular range of the damper 10 in which the tilt of the furniture F can be effectively suppressed. Then, the direction of the rod side base 22 is corrected so that the shaft part 24A of the pin 24 of the rod side base 22 is parallel to the shaft part 24A of the pin 24 of the cylinder side base 21. This can be achieved since the cylinder 11 and the rod 13 are relatively rotatable about the central axis of the damper 10 and since the cylinder side base 21 connected to the cylinder 11 and the rod side base 22 connected to the rod 13 are also relatively rotatable about the central axis of the damper 10. Then, in this state, the connecting member 31 is detached. Thereupon, the damper 10 is extended by the pressure of the compressed gas G enclosed in the cylinder 11 so that the rod side base 22 abuts against the ceiling C as illustrated in FIG. 1. The connecting member 31 is provided to be detachable as described above and when detached, the connecting member 31 can be housed in a housing part (not illustrated) provided making use of a hollow space inside the base body 23.

At last, it is confirmed that the opening side end of the rod cover 16 is located on the side of the bottom side end relative to the opening side end of the cylinder 11. When the opening side end of the rod cover 16 is in this state, it can be determined that the overturn preventing device 1 can exert a proper damping force. For example, in the case of FIG. 1, the rod cover 16 covers an entire part of the rod 13 protruding from the cylinder 11 and about one fourth of the upper end side of the cylinder 11. In the case of FIG. 6, the rod cover 16 covers the entire part of the rod 13 protruding from the cylinder 11 although the rod cover 16 slightly covers the upper end of the cylinder 11. The states as illustrated in the FIGS. 1 and 6 show that the opening side end of the rod cover 16 is located on the side of the bottom side end of the cylinder 11 relative to the opening side end of the cylinder 11, so that it can be said that the damper 10 is capable of exerting a proper damping force. In this state, the piston 14 is immersed in the hydraulic fluid L so that the damper 10 can exert a proper damping force. Accordingly, it can be determined that the overturn preventing device 1 is mounted in a state where the damper 10 can exert a proper damping force.

On the other hand, as illustrated in FIG. 7, when the opening side end of the rod cover 16 is farther away from the bottom side end of the cylinder 11 than the opening side end of the cylinder 11, the overturn preventing device 1 is not in the state where the damper 10 can exert a proper damping force, so that it can be determined that the overturn preventing device 1 is not mounted in the state where the damper 10 can exert a proper damping force. In other words, the piston 14 is not disposed in the hydraulic fluid L but in the compressed gas G above the hydraulic fluid L. In this case, upon occurrence of shaking of due to an earthquake or the like, a proper damping force cannot work until the damper 10 is contracted so that the piston 14 is moved into the hydraulic fluid L, with the result that the furniture F may be overturned. Hence, the mounting of the overturn preventing device 1 should be reconsidered.

As described above, the overturn preventing device 1 is mounted between the top surface of the furniture F installed on the installation surface and the ceiling C. The overturn preventing device 1 includes the damper 10. The damper 10 includes the cylinder 11, the rod 13 and the rod cover 16. The cylinder 11 is formed into a cylindrical shape. The rod 13 is inserted into the cylinder 11 to be reciprocable in the central axis direction while protruding from one end of the cylinder 11. The rod cover 16 is formed into the cylindrical shape and extends on a central axis line of the rod 13. One end of the rod cover 16 is connected to the distal end side of the rod 13 so as to be reciprocable in the central axis direction of the rod 13 together with the rod 13. In the state where the damper 10 can exert a proper damping force, the opening side end that is the other end of the rod cover 16 is located on the side of the bottom side end of the cylinder 11 relative to the opening side end of the cylinder 11.

According to the above configuration, in the overturn preventing device 1 of the first embodiment, by confirming the location of the opening side end of the rod cover 16, it can be easily determined whether or not the damper is in a state of capable of exerting a proper damping force, that is, whether or not the piston 14 is immersed in the hydraulic fluid L which means the state capable of exerting proper damping force in the hydraulic damper.

Accordingly, it can be easily determined whether or not the overturn preventing device 1 is properly mounted.

Furthermore, the damper 10 includes the piston 14 housed in the cylinder 11 to be slidable in the central axis direction. The proximal end of the rod 13 is connected to the piston 14. The hydraulic fluid L and the compressed gas G are enclosed in the cylinder 11. The rod 13 protrudes upward from the cylinder 11. The piston 14 is immersed in the hydraulic fluid L when the damper 10 is in a state capable of exerting a proper damping force. In this case, by confirming the location of the rod cover 16, it can be determined whether or not the damper 10 which is a hydraulic damper is in a state capable of exerting a proper damping force, that is, whether or not the piston 14 is immersed in the hydraulic fluid L.

Furthermore, the overturn preventing device 1 includes the cylinder side base 21 and the connecting member 31. The cylinder side base 21 is coupled to the bottom side end of the cylinder 11 and abuts against the top surface of the furniture F. The connecting member 31 connects the cylinder side base 21 and the rod cover 16. As a result, the overturn preventing device 1 can be easily held in the state where the damper 10 is contracted. Furthermore, the connecting member 31 is provided so as to be detachable relative to the rod cover 16 and the cylinder side base 21. As a result, the connecting member 31 can be kept detached when unnecessary. Still furthermore, since the overturn preventing device 1 is provided with the housing part for housing the connecting member 31, the connecting member 31 can be prevented from being lost by being housed herein.

Furthermore, the cylinder side base 21 is coupled to the damper 10 via the pin 24 serving as the rotating shaft rotatably supporting the damper 10. The cylinder side base 21 further has the scale 23B. The scale 23B indicates the angle about the rotating shaft. The connecting member 31 is rotatably supported by the proximal end of the pin 24 serving as the rotating shaft thereby to be connected to the cylinder side base 21. The connecting member 31 has the pointer 31C. The pointer 31C is rotated with rotation of the connecting member 31. Accordingly, the inclination angle of the damper 10 about the rotation axis can be easily recognized. As a result, it can be easily determined whether or not the damper 10 is at a proper inclination angle.

Furthermore, since the damper 10 has the rod cover 16, adhesion of dust to the outer peripheral surface of the rod 13 can be suppressed. Furthermore, though it is difficult to apply decoration on the surface of the rod 13, such as by painting, it is possible to apply a desired decoration to the rod cover 16 when the damper 10 has the rod cover 16 covering the rod 13. Accordingly, since the portions where a desired decoration can be applied is increased as compared with the case where the damper has no rod cover, the designability of the overturn preventing device can be improved.

Second Embodiment

Next, a second embodiment will be described with reference to FIG. 8 and the like. The overturn preventing device 201 of the second embodiment as illustrated in FIG. 8 and the like differs from the overturn preventing device 1 of the first embodiment in that the cylinder 211 has cylinder body 211C and protrusions 211D protruding from an open end of the cylinder body 211C in the central axis direction of the cylinder 211. The overturn preventing device 201 of the second embodiment substantially has the same construction and the same functions in the other respects as in the first embodiment. Therefore, parts in the other respects are labeled by the same reference symbols as those in the first embodiment, and detailed description of these parts will be eliminated. Furthermore, the furniture F installed on the installation surface is exemplified as the article also in the following description. However, the overturn preventing device 201 may be applied to any article other than the furniture.

The protrusions 211D are provided to protrude from an open end edge of the cylinder body 211C along an extension direction of the damper 10, as illustrated in FIG. 8. In other words, the protrusions 211D are provided to protrude upward from an upper end edge of the cylinder body 211C. That is, the protrusions 211D extend above the cylinder body 211C. In this case, the upper end of the cylinder 211 is the upper ends of the protrusions 211D. A plurality of protrusions 211D is provided (two in FIG. 8).

The overturn preventing device 201 thus constructed has the following action and effect. More specifically, the cylinder 211 has the protrusions 211D protruding at the upper end of the cylinder body 211C. Accordingly, when the damper 210 extends to the vicinity of its maximum length with which the damper 210 exerts a proper damping force, this can be easily grasped. For example, when the cylinder 211 has no protrusions 211D, it is difficult to distinguish whether or not a part covered by the rod cover 16 is the vicinity of the upper end. However, the cylinder 211 has the protrusions 211D. Accordingly, when only the protrusions 211D of the cylinder 211 are covered by the rod cover 16, it can be easily understood that the state is a vicinity of the upper end of the cylinder 211 and that the damper has a nearly maximum length in the state where the damper can exert a proper damping force. Furthermore, since the multiple protrusions 211D are provided, they are visible in a wider range.

As described above, the overturn preventing device 201 of the second embodiment has the same action and effect as of the first embodiment. In addition, it can be easily understood whether or not the damper 10 extends to have a nearly maximum length in the state where it exerts a proper damping force.

The present invention should not be limited to the embodiments described above with reference to the drawings, but the technical scope of the invention encompasses the following embodiments, for example.

(1) Although the overturn preventing device is mounted on the furniture in the first and second embodiments, the overturn preventing device may be mounted on, for example, a bed having a plurality of beds connected to each other in the up-down direction, a large sized television, a refrigerator, a book shelf, a showcase, a server rack and the like, all of which have a possibility of being overturned by shaking of an earthquake or the like. (2) Although the overturn preventing device is mounted on the furniture placed on the floor surface with the rear surface being opposed to the wall surface in the first and second embodiments, the overturn preventing device may be mounted on a piece of furniture placed on the floor surface without being adjacent to a wall. In this case, when there is a possibility that the article would be overturned not only frontward but also in other directions such as rearward, the overturn preventing device needs to be properly mounted according to a direction in which the article may be overturned, with attention to a mounting position, the number of overturn preventing devices to be mounted, an inclination angle of the damper, a direction in which the damper is inclined, etc. (3) Although the compression damper is used in the first and second embodiments, a two-way damper or an extension damper may be used. When using these dampers, the overturn preventing device needs to be properly mounted according to the type of the damper with attention to the bases to be fixed to the article and ceiling, the location or the number of the devices, the inclination angle of the damper, the inclination direction of the damper, and the like. (4) In the first and second embodiments, the damper is extended by the gas pressure of the compressed gas. However, for example, the damper may be extended by applying a biasing force by other means such as a compression coil spring, or may be further extended by a combination of the means and the like. (5) In the first and second embodiments, the liquid pressure damper is used as the damper, and the hydraulic fluid is employed as the operating liquid enclosed in the cylinder. However, for example, a liquid pressure damper enclosing another liquid such as water as the operating liquid may be employed. (6) Although the first and second embodiments show the examples in which the connecting member is provided, the connecting member is not a requisite component in the invention. Even when the connecting member is provided, the invention should not be limited to the configuration of the first and second embodiments. Any connecting member may be applied which can restrict at least one of the contracting operation and the extending operation of the damper irrespective of a connection part (engagement part), such as a connecting member connecting the rod cover and the cylinder. (7) Although the first end second embodiments exemplify the connecting member connecting the rod cover and the pin of the base, the configuration of the connecting member should not be limited to the exemplified. For example, as illustrated in FIG. 9, an engagement part 23C may be provided on the base body 23, and the engagement part 23C and the rod cover 16 may be engaged with each other by an engagement pin 32, whereby the base body 23 and the rod cover 16 are directly connected to each other. In this case, the engagement pin 32 serves as the connecting member. (8) Although the first and second embodiments show an example of the connecting member provided so as to be detachable, the connecting member may be provided so as to be undetachable at one of ends thereof. In this case, as illustrated in FIG. 10, for example, an engagement claw 23D may be formed integrally with the base body 23 and the rod cover 16 may be directly locked by the engagement claw 23D. Thus, the connecting member may be provided to be fixed to the undetachable side. Furthermore, the engagement claw 23D may be provided on the rotating shaft member such as the above-described pin so as to not to be insertable or removable but to be rotatable. In this case, the engagement claw 23D serves as the connecting member. (9) Although the connecting member is connected in a state close to where the damper is most contracted in the first and second embodiments, an amount of contraction of the damper at the time of connection should not be particularly limited. However, from the viewpoint of ease in handling such as transportation and storage, it is preferable that an amount of contraction is large, that is, an overall length is shorter. (10) Although the side surface of the base body is formed with the scale giving a rough indication of the inclination angle of the damper in the first and second embodiments, the scale is not a requisite component in the invention. When the scale is formed, the configuration of the scale should not be limited to those of the first and second embodiments. For example, the scales may be respectively formed on both side surfaces of the base body, or the scale may be formed to have both a range of 15° to 25° and a range of −15° to −25° about the rotation axis. Thus, the scales may be formed on a plurality of locations. (11) Although the pin is exemplified as the rotating shaft member in the first and second embodiments, another shaft member such as bolt may be employed, for example.

EXPLANATION OF REFERENCE SYMBOLS

-   -   C . . . ceiling; F . . . furniture (article); G . . . compressed         gas (gas); L . . . hydraulic fluid (operating liquid); W . . .         wall surface; 1, 201 . . . overturn preventing device; 10, 201 .         . . damper; 11, 211 . . . cylinder (11A . . . rod side pressure         chamber, 11C . . . counter-rod side pressure chamber, 211C . . .         cylinder body, 211D . . . protrusion); 12 . . . rod guide; 13 .         . . rod; 14 . . . piston; 15 . . . damping part (15A . . .         orifice, 15B . . . check valve); 16 . . . rod cover (16A . . .         engaged hole); 18 . . . joint (18A . . . through hole); 21 . . .         cylinder side base; 22 . . . rod side base; 23 . . . base body;         23A . . . insertion hole; 24 . . . pin; 24A . . . shaft part; 25         . . . stop ring; 26 . . . bush; 26A . . . concave part; 26B . .         . outer peripheral surface; 26C . . . inner peripheral surface;         31 . . . connecting member; 31A . . . base side engaging part;         31B . . . cover side engaging part; 31C . . . pointer; and 32 .         . . engagement pin. 

1. An overturn preventing device to be mounted between a top surface of an article installed on an installation surface and a ceiling, the device comprising a damper including: a bottomed cylindrical cylinder enclosing an operating liquid and a gas; a rod protruding upward from one of two ends of the cylinder and inserted into the cylinder to be reciprocable in a central axis direction; a piston to which a proximal end of the rod is coupled, the piston being housed in the cylinder to be slidable in the central axis direction; and a rod cover which is cylindrical and extends on a central axis line of the rod, the rod cover having two ends one of which is coupled to a distal end side of the rod thereby to be reciprocable in the central axis direction of the rod together with the rod, wherein the other end of the rod cover is located on a side of the other end of the cylinder relative to the one end of the cylinder when the piston is immersed in the operating liquid.
 2. The overturn preventing device according to claim 1, further comprising: a cylinder side base coupled to the other end of the cylinder and configured to abut against the top surface of the article; and a connecting member connecting the cylinder side base or the cylinder and the rod cover with the damper being contracted.
 3. The overturn preventing device according to claim 2, wherein the cylinder side base is coupled to the damper via a rotating shaft rotatably supporting the damper; wherein the cylinder side base has a scale indicating an angle about the rotating shaft; wherein the connecting member is rotatably supported by the rotating shaft thereby to be connected to the cylinder side base; and wherein the connecting member has a pointer which is rotated with rotation of the connecting member to point to the scale. 